Toluene

Toluene is added to gasoline, used to produce benzene, and used
as a solvent. Exposed to toluene may occur from breathing
ambient or indoor air. The central nervous system (CNS) is the
primary target organ for toluene toxicity in both humans and
animals for acute (short-term) and chronic (long-term) exposures.
CNS dysfunction and narcosis have been frequently observed in
humans acutely exposed to toluene by inhalation; symptoms include
fatigue, sleepiness, headaches, and nausea. CNS depression has
been reported to occur in chronic abusers exposed to high levels
of toluene. Chronic inhalation exposure of humans to toluene
also causes irritation of the upper respiratory tract and eyes,
sore throat, dizziness, and headache. Human studies have
reported developmental effects, such as CNS dysfunction,
attention deficits, and minor craniofacial and limb anomalies, in
the children of pregnant women exposed to toluene or mixed
solvents by inhalation. Reproductive effects, including an
association between exposure to toluene and an increased
incidence of spontaneous abortions, have also been noted.
However, these studies are not conclusive due to many confounding
variables. EPA has classified toluene as a Group D, not
classifiable as to human carcinogenicity.